A directed mutation operator for real coded genetic algorithms

Copyright @ Springer-Verlag Berlin Heidelberg 2010.Developing directed mutation methods has been an interesting research topic to improve the performance of genetic algorithms (GAs) for function optimization. This paper introduces a directed mutation (DM) operator for GAs to explore promising areas in the search space. In this DM method, the statistics information regarding the fitness and distribution of individuals over intervals of each dimension is calculated according to the current population and is used to guide the mutation of an individual toward the neighboring interval that has the best statistics result in each dimension. Experiments are carried out to compare the proposed DM technique with an existing directed variation on a set of benchmark test problems. The experimental results show that the proposed DM operator achieves a better performance than the directed variation on most test problems

The Organizational Vehicles of Islamic Political Dissent: Social Bases, Genealogies and Strategies

The organizational vehicles of Islamic political dissent vary greatly in the contemporary world. At one end of the spectrum, there could be full-fledged political parties occupying recognized positions in the official sphere of political life, and recently some of these have even come to take power in their respective countries. At the other end, however, one might find terrorist activity centred on small and isolated cells. Located somewhere in between could be a hos of mass organizations associated with religious social movements, peaceful or otherwise and in some cases, assorted militias that deal in intimidation or violence. These diverse vehicles have found different levels of success in specific contexts. It is shown here that what kinds of vehicles become predominant is largely contingent on how social alliances come to be built to represent the interests of an increasingly diverse ummah — the community of believers — in modern and profane competition over power and resources